1. Field of the Invention
The present invention generally relates to an apparatus for detecting particles on a glass surface and a detecting method thereof, and more specifically, to an apparatus for detecting particles on a glass surface and a detecting method thereof for exactly inspecting particles on a surface where micro circuit patterns are deposited, regardless of flatness.
2. Description of the Related Art
When particles exist on a glass surface used for a flat display and micro circuit patterns are deposited on these particles, it causes deterioration of the micro circuit patterns. Thus, before the micro circuit patterns are deposited, it should check whether any particles exist on a provided glass substrate (particularly, a glass surface where circuits are deposited).
Since the inspection on the surface of the glass substrate is conducted by using a camera while the glass substrate is being transferred, exact inspection is essential even though flatness of the glass substrate, which is caused during the transferring, changes. Therefore, in a prior detecting apparatus, an automatic distance adjustment device was additionally used to irradiate very thin laser illumination by giving a large slope in the transferring direction of the glass substrate, and to compensate changes of flatness of the glass substrate. The prior detecting apparatus for particles, however, has some restrictions on deciding whether particles are attached to a glass surface (upper side) where circuits are deposited, or to a glass surface (lower side) where the circuits are not deposited. Furthermore, accuracy of inspection was influenced by the changes of the flatness of the glass substrate.